1. Field of the Invention
The present invention relates to a data storage device, or disk drive, for receiving a removable disk cartridge. More particularly, the present invention relates to a movable platform disposed in the data storage device and on which critical drive components are mounted to achieve close tolerances and simplify testing.
2. Description of the Prior Art
Removable disk cartridges for storing digital electronic information typically comprise an outer casing or shell that houses a rotatable recording medium, or disk, upon which electronic information can be stored. The cartridge shell often comprises upper and lower halves that are joined together to house the disk. The disk is mounted on a hub that rotates freely within the cartridge. When the cartridge is inserted into a disk drive, a spindle motor in the drive engages with the disk hub in order to rotate the disk within the cartridge. The outer shell of the cartridge typically has some form of opening near its forward edge to provide the recording heads of the drive with access to the recording surfaces of the disk. A shutter or door mechanism is often provided to cover the opening when the cartridge is not in use to prevent dust or other contaminants from entering the cartridge and settling on the recording surface of the disk.
Disk drives for receiving removable disk cartridges, including conventional 3.5" floppy disk drives, must have some mechanism for bringing the hub of a disk cartridge into engagement with the spindle motor of the disk drive and for maintaining tight tolerances between the cartridge hub, spindle motor and magnetic head actuator of the disk drive. In many conventional floppy disk drives, a floppy disk cartridge is guided vertically into engagement with the spindle motor of the drive which is rigidly mounted to a base plate in the disk drive. The head actuator is also mounted to the base plate. With this arrangement, it is difficult to ensure critical tolerances and spacing between the disk cartridge, the head actuator and the spindle motor.
In other disk drives, such as that described in U.S. Pat. Nos. 4,663,677 and 5,317,464, the head actuator is fixedly attached to a base plate within the disk drive, but the spindle motor is mounted in a translating mechanism that translates the spindle motor vertically into engagement with the hub of a disk cartridge after the cartridge is fully inserted in the drive, while these mechanisms have their advantages, they are mechanically complex. Moreover, the movement of the spindle motor in relation to the head actuator makes it difficult to achieve critical tolerances between the disk cartridge, spindle motor and head actuator.
As the foregoing illustrates, there is a need for an improved apparatus for bringing a disk cartridge into engagement with the spindle motor of a disk drive and for accurately positioning a disk cartridge relative to the spindle motor and magnetic head actuator of a disk drive. Additionally, it would be advantageous if the improved mechanism could be assembled as a stand-alone, fully testable sub-assembly. The present invention satisfies these needs.